From mboxrd@z Thu Jan 1 00:00:00 1970 From: ppluzhnikov@google.com (Paul Pluzhnikov) Subject: [PATCH torvalds/linux.git] Make linux/tcp.h C++ friendly (trivial) Date: Sat, 9 Jun 2012 07:53:03 -0700 (PDT) Message-ID: <20120609145303.3094919060E@elbrus2.mtv.corp.google.com> Cc: ppluzhnikov@google.com, Jiri Kosina , David Miller To: netdev@vger.kernel.org Return-path: Received: from mail-wg0-f74.google.com ([74.125.82.74]:61697 "EHLO mail-wg0-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751012Ab2FIOxG (ORCPT ); Sat, 9 Jun 2012 10:53:06 -0400 Received: by wgbdt11 with SMTP id dt11so152400wgb.1 for ; Sat, 09 Jun 2012 07:53:04 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: From: Paul Pluzhnikov I originally sent this patch to , but Jiri Kosina did not feel that this is fully appropriate for the trivial tree. Using linux/tcp.h from C++ results in: cat t.cc #include int main() { } g++ -c t.cc In file included from t.cc:1: /usr/include/linux/tcp.h:72: error: '__u32 __fswab32(__u32)' cannot appear in a constant-expression /usr/include/linux/tcp.h:72: error: a function call cannot appear in a constant-expression ... Attached trivial patch fixes this problem. Tested: - the t.cc above compiles with g++ and - the following program generates the same output before/after the patch: #include #include int main () { #define P(a) printf("%s: %08x\n", #a, (int)a) P(TCP_FLAG_CWR); P(TCP_FLAG_ECE); P(TCP_FLAG_URG); P(TCP_FLAG_ACK); P(TCP_FLAG_PSH); P(TCP_FLAG_RST); P(TCP_FLAG_SYN); P(TCP_FLAG_FIN); P(TCP_RESERVED_BITS); P(TCP_DATA_OFFSET); #undef P return 0; } Thanks, P.S. Google has blanket copyright assignment to FSF. Signed-off-by: Paul Pluzhnikov --- diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 4c5b632..5f359db 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -69,16 +69,16 @@ union tcp_word_hdr { #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3]) enum { - TCP_FLAG_CWR = __cpu_to_be32(0x00800000), - TCP_FLAG_ECE = __cpu_to_be32(0x00400000), - TCP_FLAG_URG = __cpu_to_be32(0x00200000), - TCP_FLAG_ACK = __cpu_to_be32(0x00100000), - TCP_FLAG_PSH = __cpu_to_be32(0x00080000), - TCP_FLAG_RST = __cpu_to_be32(0x00040000), - TCP_FLAG_SYN = __cpu_to_be32(0x00020000), - TCP_FLAG_FIN = __cpu_to_be32(0x00010000), - TCP_RESERVED_BITS = __cpu_to_be32(0x0F000000), - TCP_DATA_OFFSET = __cpu_to_be32(0xF0000000) + TCP_FLAG_CWR = __constant_cpu_to_be32(0x00800000), + TCP_FLAG_ECE = __constant_cpu_to_be32(0x00400000), + TCP_FLAG_URG = __constant_cpu_to_be32(0x00200000), + TCP_FLAG_ACK = __constant_cpu_to_be32(0x00100000), + TCP_FLAG_PSH = __constant_cpu_to_be32(0x00080000), + TCP_FLAG_RST = __constant_cpu_to_be32(0x00040000), + TCP_FLAG_SYN = __constant_cpu_to_be32(0x00020000), + TCP_FLAG_FIN = __constant_cpu_to_be32(0x00010000), + TCP_RESERVED_BITS = __constant_cpu_to_be32(0x0F000000), + TCP_DATA_OFFSET = __constant_cpu_to_be32(0xF0000000) }; /*